Engine



Aug. 6, 1935.

C.N.'FURAY ENGINE Filed Nov. 27, 1953 3 Sheets-Sheet 2 INVENTOR.

Carl NFuray A ATTORNEY.

C. N. FURAY Aug. 6, 1935.

ENGINE Filed Nov. 27, 1933 3 Sheets-Sheet 3 INVENT OR. Carl A? F anz g/ ATTORNEY.

Patented Aug. 6, 1935 PATENT OFFICE ENGINE Carl N. Furay, Dayton, Ohio, assignor to Gen-- tinental Motors Corporation, Detroit, Mich a corporation of Virginia Application November 27, 1933, Serial No. 699,848 I 8 Claims. ((31. 12341) My invention relates to engines and more particularly to engines of the type adapted for propelling aircraft and for other similar purposes. In its more particular, aspects, my invention is related to an engine of the type having opposed cylinders and which is so arranged and constructed as to provide for reverse engine operation with a minimum of change or disassembly of the essential component elements ofthe engine structure. 1

There are many instances where it is desirable to reverse the rotation of the engine, this characteristic being often necessary in engines of the type employed for aircraft, especially with that type of aircraft having more than a single engine, in which case it is desirable to'employ engines which are operated in opposite directions. Heretofore in providing engines which are adapted to be reversed, it has been necessary to pro-- vide many additional parts ,of the engine which need to be replaced by other engine parts of a. different design, or by relatively shifting or adjusting certain of the parts of said engine structure, inother words, a major disassembly of the engine is necessary to effect this change.

It is an object of my-present invention to provide an internal combustion engine'which is so constructed and arranged as to be assembled to provide for operation in one direction, but which may be reversed withouta major disassembly of the cylinders and other elements of the engine structure associated therewith.

Another object of my present invention is to provide a structure having interchangeable parts whereby to facilitate the assembly and manufacture of the engine, and to adapt said engine for efficient assembly with an airplane structure requiring engines which are oppositely rotated, the

present invention pertaining to an engine having multiple banks of cylinders having the camshafts respectively provided with spaced cams having profiles of substantially the same contour, whereby the rocker arms associated with said camshafts may be interchanged with a minimum of effort and without requiring a major disassembly or selective adjustment of the engine camshaft.

A further object of my present invention is to provide an improved engine structure in which the rocker arms respectively associated with the intake and exhaust valves may be readily and quickly interchanged.

, More particularly it is an object of my present invention to provide an engine structure having opposed banks of aligned cylinders and a cooperating valving mechanism which is so constructed as to permit the interchange of rocker arms from one bank of cylinders to the other bank of cylindersfor reversing the direction of rotation of said engine, and permitting the said re-arrangement of the engine elements with no major disassembly of the engine structure.

For a more detailed understanding of my invention, reference may be had to the accompanying drawings which illustrate one form which my invention may assume, and in which:

Fig. l is a plan view of an engine constructed in accordance with my invention and showing the engine as being secured to a rigid part of the airplane structure, 7

Fig. 2 is an elevational view of the valve actuating mechanism, said View showing the engine camshaft and associated rocker arms, the cover of said rocker arm housing being removed to facilitate the illustration of the principles of my invention,

Fig. 3 is a similar elevational View of the engine, which is clearly illustrative of the novel feature-of my present invention in which the rocker arms of another bank of cylinders has been substituted for the rocker arms as illustrated in Fig. 2,

Fig. 4 is a detailed sectional view'of the engine structure showing a cylinder which is typical of those contained within one bank, and which clearly illustrates the valve actuation, this figure being taken substantially on the line 4-4 of Fig. 2,

Fig. 5 is a detailed sectional view of a typical engine cylinder showing the valve relation in an engine in which the rocker arms of another bank of cylinders have been interchanged with those illustrated in Fig. 4 for the purpose of reversing the direction of rotation of said engine,

Fig. 6 is a transverse sectional and diagrammatic view of an engine having opposed cylinders, said engine being illustrated somewhat diagrammatically to illustrate the principles of the invention, and V Fig. '7 is a semi-sectional and diagrammatic view of the engine similar to the showing in Fig. 6, but illustrating the interchangeable feature of the rocker arms whereby to reverse the direction of rotation of said engine operation.

I have shown in the accompanying drawings an embodiment of my invention, in which the principles illustrated are embodied in an engine of the type having opposed cylinders. It will be obvious that the principles of my invention may be incorporated in engines other than those of the type shown, thoughI find that a construction of the character described herein and covered by the appended claims is particularly adapted for my present invention.

I have illustrated an engine A which in general includes a crankcase structure it? to which a pair of banks of aligned cylinders are adapted to be secured. One bank of said cylinders is designated by the reference character B while the other bank is preferably designated by the reference character B. These banks of cylinders B and B preferably include a plurality of aligned cylinders H and M respectively, which are adapted to be secured to the crankcase in the usual manner. A cylinder head structure C is secured to the cylinders l 5 while the cylinder head structure C is secured to the cylinders i 6, these cylinder head structures being secured to the cylinder structures in the usual manner.

In the particular embodiment of my invention I have shown the cylinders as being horizontally opposed, but obviously the principles of my invention as described and claimed herein are not particularly limited to use with an engine of this particular type. It will be noted in the present embodiment of my invention, that the camshafts l2 and 52 are respectively carried or otherwise supported by the cylinder head structures C and C, each of these camshafts carrying suitable cams having profiles of substantially the same contour, these cams being spaced longitudinally of the camshaft and being constructed for actuating the intake and exhaust valves l3, M and l3, M of cylinders i! and H respectively.

It will be noted that the cams 9 and 9, which are respectively carried by the Camshafts l2 and I2 are symmetrically arranged and so constructed as to provide camshafts which are alike, that is, the cam contour and cam spacing are alike. The reversal of the engine is had by interchanging the rocker arms I5 in one bank of engine cylinders with the rocker arms I5 of the other bank of engine cylinders, the timing of the engine being adjusted for the reason that the firing order is reversed on reversing the engine.

I preferably term these camshafts l2 and I2 right and left hand camshafts, since I find that in many instances it is not desirable to interchange the camshafts, due principally to the necessity of then revising the accessory drives. The cam shafts are substantially alike in all respects and could be interchanged by interchanging the connections with the "accessories. But to avoid the necessity of interchanging accessories, it is found more desirable to provide these right and left hand camshafts which are alike with the exception of the associated accessory drives.

It will be obvious that the principles of my invention may be incorporated in engines of the type having interchangeable camshafts if so desired, it being understood however that the engine timing would then be further revised or altered and that the accessory drives must be further changed and re-arranged.

It will be noted that the intake and exhaust valves of the engine are respectively located on opposite sides of an engine longitudinal plane containing the cylinder axes, and that the camshaft is preferably extended longitudinally of the engine. The cams 9 and 8' are constructed to lie substantially intermediate the valves because the axis of said camshaft is contained substantially within the longitudinal engine plane containing the cylinder axes.

It will be noted in Fig. 2 that the rocker arms I5 operatively connecting cam shaft l2 with the intake and exhaust valves is and I4 are constructed alike, but are arranged to extend in opposite directions from the cam shaft, the offset of said arms being thus oppositely arranged for engagement with cams 9 which are spaced longitudinally of the camshaft. These intake and exhaust cams are respectively located on opposite sides of a transverse engine plane containing the valve axes. The rocker arms l5 shown in Fig. 2 which are substantially identical in construction, can thus be interchanged with each other.

The cams carried by the camshaft which are of substantially the same construction, can be employed for actuating either the intake valve or the exhaust valve. While one bank of cylinders is provided with a rocker arm structure of one type and more particularly referred to as right hand rocker arms, the other bank of cylinders is provided with rocker arms 55 of the type which are hereinafter referred to as left hand rocker arms. The distinction between these rocker arms l5 and i5 is that while the inner end portion of the rocker arm I5 is offset in one direction as at 8, the rocker arms i5" associated with the other bank of cylinders are each offset in an opposite direction as at 8.

Since both camshafts which are associated with the banks of aligned cylinders, are preferably constructed substantially identical, and are provided with cams having profiles of substantially the same contour, it will be noted that the right and left hand rocker arms of the banks of cylinders may be respectively interchanged, in which case the assembly takes the form as particularly illustrated in Fig. 3 which is opposite to the arrangement in Fig. 2 and provides for reverse engine operation.

It will be particularly noted that when it is desired to provide an engine in which the direction of rotation is reversed, that it is not necessary to provide a major disassembly of the engine, since the camshafts of both banks of cylinders are substantially the same and the cams are such a character as to permit the operation of the intake and exhaust valves for reverse engine operation without the necessity of replacing the camshaft or without the necessity of shifting or otherwise adjusting the position of the camshaft. It will be apparent that the various accessories, which are customarily assembled with engines of the present character, will be necessarily interchanged or otherwise positioned so as to obtain the correct operation, but it will be further noted that by employing my present construction that it is not necessary to provide different drives for the accessories in all cases. The only major change in reversing the engine drive in addition to the slight rearrangement of the accessories, is to interchange the rocker arms of one bank of cylinders with those of the other bank of cylinders, and it will be noted on observing Figs. 2 and 3 that the rocker arms l5 shown in Fig. 2 are replaced by the rocker arms l5. Thus earn 9 which actuated the intake valve is now utilized for actuating the exhaust valve in Fig. 3, this being made possible by the fact that the said cams are provided with profiles of substantially the same contour.

It will be noted that the engine crankshaft 20 is provided with a crank 2i to which the connect ing rods 22 and 22 which are extended substantially in opposite directions are connected. These connecting rods 22 and 22 are respectively connected with the pistons 23 and 23' adapted for operation in the opposed cylinders H and II.

The timing of the engine is such as to preferably provide for a spacing in the engine cyclical events of opposed cylinders of substantially 180 degrees of crankshaft rotation. In this connection it will be noted that the piston 23 is moving outwardly of the cylinder while the piston 23 is moving inwardly of the cylinder. Thus, the valving mechanism associated with cylinder l l is arranged to be exhausting as shown in Fig. 6 while the valving mechanism associated with cylinder l I is arranged to be intaking, the exhaust stroke of cylinder ll being spaced substantially 180 'degrees of crankshaft rotation behind the exhaust stroke of the cylinder ll. On interchanging the rocker arms of one bank of engine cylinders to the other bank of cylinders, (see Fig. 7) it will be noted that the direction of rotation of the crankshaft is reversed, and also the direction of rotation of the camshaft. The relative positioning of the crankshaft and camshafts is the same in Fig. 7 as in Fig. 6, but because of the interchange of rocker arms it will be noted that the cylinder H is now intaking while the cylinder H is now exhausting.

Thus by reason of a simple interchange of rocker arms of one bank of cylinders with the rocker arms of the other bank of cylinders, the direction of engine rotation may be reversed without a major disassembly of the engine and with a minimum of time and labor. Furthermore, it will be readily apparent that the manufacture of reversible engines is considerably simplified by my invention.

It Will be apparent to those skilled in the art to which my invention pertains that various modifications and changes may be made therein without departing from the spirit of my invention or from the scope of the appended claims.

What I claim as my invention is:

1. In an internal combustion engine of the type having a plurality of aligned cylinders, a valve actuating mechanism for said engine and including a cam shaft extending substantially longitudinally of the engine, intake and exhaust valves for each cylinder respectively supported on opposite sides of the longitudinal engine plane containing the cylinder axes, intake and exhaust cams carried by said cam shaft for respectively actuating said intake and exhaust valves, said cams being spaced longitudinally of the camshaft and having profiles of substantially the same contour, oppositely extending interchangeable rocker arms engaging said cams and operatively connected with said intake and exhaust valves, and bearing means for supporting said rocker arms, the center of said bearing means being substantially contained in a transverse engine plane containing the cylinder and valve axes.

2. In an internal combustion engine of the type having a plurality of aligned cylinders, a valve actuating mechanism for said engine and including a cam shaft extending substantially longitudinally of the engine, intake and exhaust valves for each cylinder respectively supported on opposite sides of the longitudinal engine plane containing the cylinder axes, intake and exhaust cams carried by said cam shaft for respectively actuating said intake and exhaust valves, said cams being spaced longitudinally of the cam shaft and having profiles of substantially the same contour, the intake and exhaust cams for each cylinder being respectively located on opposite sides of a transverse engine plane containing the intake and exhaust valve axes, and oppositely extending interchangeable pivotally supported rocker arms of identical construction for operatively connecting said intake and exhaust valves with the intake and exhaust cams respectively, and bearing means for supporting said rocker arms, the center of said bearing means being substantially contained in a transverse engine plane containing the cylinder and valve axes.

3. In an internal combustion engine of the type having a plurality of banks of aligned cylinders. a valve actuating mechanism for each bank of engine cylinders and each including a cam shaft, intake and exhaust'valves for each cylinder respectively supported on opposite sides of a longitudinal engine plane containing the cylinder axes, cams carried by'the cam shaft for actuating said intake and exhaust valves and all having profiles of substantially the same contour, right hand rocker arms operatively connecting the cams and valves of one bank of cylinders, and left hand rocker arms operatively connecting the cams and valves of another'bank of cylinders, the rocker arms of one bank of cylinders being interchangeable with the rocker arms of the other bank of cylinders for reversing the direction of rotation of said engine.

4. In an internal combustion engine of the type having a plurality of banks of aligned cylinders, a valve actuating mechanism for each bank of engine cylinders and each including a cam shaft, intake and exhaust valves foreach cylinder respectively supported on opposite sides of a longitudinal engine plane containing the cylinder axes, cams carried by the cam shaft for actuating said intake and exhaust valves and all having profiles of substantially the same contour, right rotation of said engine.

5. In an internal combustion engine of the type having a plurality of banks of aligned cylinders, a valve actuating mechanism for each bank of engine cylinders and each including a cam shaft, intake and exhaust valves for each cylinder respectively supported on opposite sides of a longitudinal engine plane containing the cylinder axes, cams carried by the cam shaft for actuating said intake and exhaust valves and all having profiles of substantially the same contour, right hand rocker arms operatively connecting the cams and valves of one bank of cylinders, and left hand rocker arms operatively connecting the cams and valves of another bank of cylinders, said right hand rocker arms of one bank of cylinders being interchangeable with the left hand rocker arms of said other bank of cylinders for reversing the direction of rotation of the engine.

6. In an internal combustion engine of the type having substantially opposed banks of aligned cylinders, a valve actuating mechanism for each bank of engine cylinders and each including a cam shaft, intake and exhaust valves for each cylinder respectively supported on opposite sides of a longitudinal engine plane containing the cylinder axes, cams carried by the cam shaft for actuating said intake and exhaust valves and all having profiles of substantially the same contour, oppositely extending right hand rocker arms operatively connecting the cams and valves of one bank of cylinders, and oppositely extending left hand rocker arms operatively connecting the cams and valves of another bank of cylinders, said right hand rocker arms of one bank of cylinders being interchangeable with the left hand rocker arms of said other bank of cylinders for reversing the direction of rotation of the engine.

'7. In an internal combustion engine having opposed cylinders, intake and exhaust valves for said cylinders, a crankshaft, a cam shaft for each cylinder and driven by said crankshaft, separate intake and exhaust cams carried by each cam shaft and having profiles of substantially the same contour, right hand rocker arms operatively connecting the cams and valves of one bank of cylinders, and left hand rocker arms operatively connecting the cams and valves of another bank of cylinders, said right and left hand rocker arms being interchangeable from one cam shaft to the other for reversing the direction of rotation of said engine.

8. In an internal combustion engine having substantially opposed cylinders, intake and exhaust valves for each of said cylinders, a crankshaft common to said cylinders, right and left hand cam shafts respectively for each cylinder and driven by said crankshaft, separate intake and exhaust cams carried by each cam shaft and having profiles of substantially the same contour, right hand rocker arms operatively connecting the cams and valves of one bank of cylinders, and left hand rocker arms operatively connecting the cams and valves of another bank of cylinders, said right and left hand rocker arms being interchangeable from one cam shaft to the other for reversing the direction of rotation of said engine, said right and left hand cam shafts remaining fixed in the assembly.

CARL N. FURAY. 

